change IPTV Url test to consider RTSP without explicit port as valid

Found by Nicolas Niclausse
Refs #11949

(cherry picked from commit a93e14d3f528328e8e280c54003fb2a4bc4d47aa)

Conflicts:
	mythtv/libs/libmythtv/test/test_iptvrecorder/test_iptvrecorder.h
strip whitespace when splitting RTSP OPTIONS

Patch by Nicolas Niclausse
Refs #11949

(cherry picked from commit 2131558d64e269cb0b700f4faf126e4fca9b2d47)
RTSP session-id is NOT a number but a random string of at least 8 chars

Patch by Nicolas Niclausse
Refs #11949

(cherry picked from commit 864bbe0e65c4be9275aac5e1dfb362fd5bf65aab)
cppcheck: silence "Redundant assignment of ' bt8' to itself."

comment out name of unused parameter instead

(cherry picked from commit 08399fee8017438f43bec4fd6f0b0dc43f1ef2ac)
remove duplicate initialization of m_use_rtp_streaming

(cherry picked from commit a013ddace7a3137a8988f5dd8d8022f35549d792)
Rework IPTV and RTSP recorders

Lots of issues fixed and addition of missing (but required) features

- Add IPv6 support
- Handle RTCP channel (not 100% sure it’s the right information sent, but it allows to keep alive the connection with some server, and doesn’t impact playback)
- Handle Keep Alive and maintain the RTSP TCP connection life so the rtsp server doesn’t drop us (seen with VLC rtsp server and FreeBox IPTV stream)
- Can use hostnames in URL instead of just IP addresses
- Proper support of rtsp’s SDP

Fixes #11949

(cherry picked from commit 57b64c4af16aedee1608119f8e68ee01e2343d6f)

Conflicts:
	mythtv/libs/libmythtv/recorders/iptvstreamhandler.cpp
Fix compilation error

(cherry picked from commit ea57f3bbafff496f09e4369ff46886f2a4d88f9b)